This study aims to explore the association between the features of epicardial adipose tissue (EAT) in different zones and premature ventricular complexes (PVCs) originating from different sites by computed tomography (CT). A total of 136 patients who underwent radiofrequency ablation for PVCs were incorporated in this study. One hundred and thirty-six matched controls were included in this study using the case-control method (1:1 matching). PVCs were classified into four subgroups: (1) right ventricular outflow tract (RVOT-PVCs), (2) non-RVOT of the right ventricle (RV-PVCs), (3) left ventricular outflow tract (LVOT-PVCs), and (4) non-LVOT of the left ventricle (LV-PVCs). The volume and density of EAT were quantified by CT. Patients with PVCs had a significantly higher volume and lower density of EAT than the controls (P < 0.001). The LVOT-PVCs and LV-PVCs had a higher left ventricle periventricular EAT volume (LV-EATv) proportion (P < 0.05). The right ventricle periventricular EAT volume (RV-EATv) proportion was higher in ROVT-PVCs and LVOT-PVCs (P < 0.05). RVOT-PVC patients had a higher volume ratio and a smaller density differential (P < 0.05). Patients with LVOT-PVCs had a lower volume ratio and the LV-PVCs showed a greater density differential (P < 0.05). Higher volume and lower density of EAT were significantly associated with frequent PVCs. The RVOT-PVC patients had a higher volume ratio and a smaller density differential. The LVOT-PVCs had a lower volume ratio and the LV-PVCs showed a greater density differential. These suggest a link between EAT structural properties and PVCs and a potential role for regional EAT in the development of PVCs.
Diabetic cardiomyopathy (DCM) begins with a subclinical stage featuring cardiac hypertrophy, fibrosis, and disrupted signaling. These changes, especially fibrosis and stiffness, often lead to clinical heart failure. The mechanism involves metabolic dysregulation, oxidative stress, and inflammation, leading to cardiac damage and dysfunction. During the progression of the disease, the myocardium senses surrounding mechanical cues, including extracellular matrix properties, tensile tension, shear stress, and pressure load, which significantly influence the pathological remodeling of the heart through mechanotransduction. At the molecular level, the mechanisms by which mechanical cues are sensed and transduced to mediate myocardial mechanical remodeling in DCM remain unclear. The mechanosensitive transcription factors YAP and TAZ fill this gap. This article reviews the latest findings of how YAP and TAZ perceive a wide range of mechanical cues, from shear stress to extracellular matrix stiffness. We focus on how these cues are relayed through the cytoskeleton to the nucleus, where they trigger downstream gene expression. Here, we review recent progress on the crucial role of YAP and TAZ mechanotransduction in the pathological changes observed in DCM, including myocardial fibrosis, hypertrophy, inflammation, mitochondrial dysfunction, and cell death.
Background: Diabetic cardiomyopathy (DCM) is a serious cardiovascular complication specific to diabetes mellitus, with rising global prevalence. Ferroptosis, an iron-dependent form of regulated cell death driven by lethal lipid peroxidation, has been implicated in the pathogenesis of DCM. However, the key regulatory genes remain poorly characterized. This study aimed to identify and validate ferroptosis-related signature genes in DCM. Methods: Three murine transcriptomic datasets (GSE123975, GSE155377, and GSE210611) were retrieved from GEO and merged after batch correction. Differentially expressed genes were intersected with weighted gene co-expression network analysis disease-associated module genes and FerrDb ferroptosis annotations to define the ferroptosis-related differentially expressed gene candidate pool. LASSO regression and random forest selection then prioritized hub genes, defined operationally as candidates consistently prioritized by both machine-learning algorithms rather than by network-topological centrality. Classification performance was evaluated by ROC analysis and validated in two independent cohorts (GSE161931 and GSE274500). mMCPcounter estimated immune and stromal infiltration. ScRNA-seq (GSE290095) and spatial transcriptomic (GSE290094) profiling characterized cellular distribution, predicted cardiomyocyte network perturbations and tissue-level expression patterns. High-fat diet/streptozotocin (HFD/STZ)-induced DCM rat models provided experimental validation. Results: Acot1 and Txnip were identified as hub genes, with strong discriminatory performance in the discovery cohort (AUC = 1.000 and 0.988; in-sample estimates, n = 26) and independent external validation (AUC = 0.951 and 0.988). Immune profiling linked both genes inversely with vessel scores, and Txnip was also linked with eosinophils. Single-cell analysis localized Acot1 enrichment to cardiomyocytes and endothelial cells, while Txnip was broadly expressed across multiple cell types, with elevated levels in DCM. In silico knockout analysis predicted distinct cardiomyocyte network perturbation profiles for Acot1 and Txnip, and spatial transcriptomics revealed modest but disease-specific spatial associations between hub gene expression and ferroptosis driver scores (Acot1: rho = 0.123; Txnip: rho = 0.154). Both genes were significantly upregulated at mRNA and protein levels in HFD/STZ-induced DCM rats, with concurrent GPX4 depletion, ACSL4 accumulation, and FTH1 reduction consistent with ferroptosis activation. Conclusions: This study identifies Acot1 and Txnip as ferroptosis-related molecular signatures in DCM and provides multistep prioritization and validation spanning bulk transcriptomics, single-cell and spatial transcriptomics, and in vivo experimental verification, offering potential targets for ferroptosis-targeted therapeutic intervention.